Millimetre-wave radar is an emerging technique for non-destructive testing: it is less costly than X-rays and has no ionizing radiation. Compared to ultrasound it does not require the device under test to be immersed in water. This article presents methods for high-resolution millimetre-wave radar imaging without a priori knowledge of the object's shape. A polymer device with simulated material defects is examined, which could be depicted precisely.

Millimetre-wave radar is an emerging technique for non-destructive testing: it is less costly...